Optimal Design of a Deeply Embedded Ring Anchor in Soft Clay Overlying Bedrock under Vertical Loading
Publication: Geo-Congress 2023
ABSTRACT
Offshore wind energy can play a significant role in addressing the clean energy policy goals of several countries, where floating offshore wind turbines (FOWT) can be preferred over the conventional fixed bottoms due to the water depth in the envisioned region. Since attractive sites for FOWTs will be located in extensive space in deep water, the potential sites are likely dominated by heterogeneous soils, such as clay to sand. This may require several anchor alternatives depending on soil type, resulting in increased costs and complexities of the single project. Therefore, the deeply embedded ring anchor (DERA) system has developed as a cost-effective solution for mooring FOWTs due to its attractive features: its installability in any soil type, its ability to be deeply embedded, availability to attach to various mooring systems, its multiline potential, and its compact size with high load capacity. In order to investigate the applicability of the DERA to various soil conditions in a specific site, this paper conducts a comparative example study and suggests the optimal design of the DERA in given site conditions. The findings from the study provide a platform to select a mooring system considering geometric constraints and estimate the required physical features of the DERA for achieving the needed load capacity. The results show that the DERA is a feasible and cost-effective alternative for the heterogeneous seabed, shallow water depth, and thin sediment layer due to its attractive features.
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Geo-Congress 2023
Pages: 133 - 142
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Published online: Mar 23, 2023
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